Show:
Things that Go Boom!
Chemical Reactions
Chemical Reactions and Equations
Acids and Bases
States of Matter
100
Litmus paper changes color to indicate if a solution is acidic, neutral, or basic. In an acidic solution, litmus paper turns ___________. A) purple B) red C) blue D) pink
What is B. Litmus paper turns red to indicate acid.
100
Which of the following is a chemical reaction? A) Water freezes. B) Sugar dissolves in water. C) Salt and pepper are mixed in a dish. D) Iron rusts.
What is D, iron rusts.
100
A balanced chemical equation is one in which: A) the number of atoms of each element is the same in both the reactants and the products. B) the same compounds are present in both the reactants and the products. C) the reactants and the products have equal densities. D) the reactants and the products have equal volumes.
What is A) the number of atoms of each element is the same in both the reactants and the products.
100
An acid and a base will mix to form a neutral and ______________. A) a strong acid B) a salt C) a metal D) a strong base
What is B. A salt is any ionic compound that can be made from the neutralization of an acid and base.
100
1) A teapot filled with water is heated on the stove. What does the heat from the stove do to the molecules of water in the teapot? A) It makes them move slower. B) It makes them move faster. C) It makes them stay in place. D) It makes them take the shape of the teapot.
What is B. As heat from the stove increases, the water molecules within the teapot move faster.
200
When a solid is heated to its melting point, __________. A) its molecules stop moving B) it evaporates C) it freezes D) it changes to a liquid
What is D. A solid will change to a liquid when it is heated to its melting point temperature.
200
Which is an example of a physical change? A) Sodium and chlorine form salt. B) A silver ring turns black when it tarnishes. C) A log burns in the fire. D) A woman creates a sand sculpture at the beach.
What is D. A physical change can alter the appearance of a substance, but it does not change the substance itself.
200
When two substances were combined, bubbles were produced and the temperature dropped. This most likely means that: A) a chemical reaction took place. B) the two substances had low boiling points. C) one substance dissolved in the other. D) the two substances are non-reactive.
What is A) a chemical reaction took place.
200
Which statement about acids is true? A) An acid is any substance that will produce hydrogen ions (H+) in water. B) An acid will form hydroxide ions in water. C) Bases will form hydrogen acids in water. D) Bases will form carbon ions in water.
What is A. Acids in water separate into a negative and hydrogen ion (H+).
200
The body's ability to cool itself by sweating is an example of which change of state of matter? A) evaporation B) sublimation C) melting D) freezing
What is A. Energy from the body is used to evaporate sweat from the skin. When that energy is lost, the person feels cooler.
300
Any substance that produces hydroxide ions in water is known as ________________. A) an acid B) a hydrogen ion C) a base D) a neutral
What is C. Bases will react with water to release a hydroxide ion and hydrogen ion.
300
Why are bases also known as alkalis? A) Alkali is the Greek word for "base." B) Alkalis have a high concentration of hydrogen ions when put in water. C) Alkalis have a sour taste. D) Alkalis have a very low concentration of hydrogen ions when put in water.
What is D. Alkalis have a pH higher than 7 and they release very few hydrogen ions in a water.
300
What type of chemical reaction occurs when two elements form to make a compound? A) decomposition B) acid-base C) subtraction D) synthesis
What is D. A synthesis reaction occurs when two or more reactants form one product.
300
Which of the following substances is the strongest acid? A) soda, pH 3 B) tomatoes, pH 4.5 C) stomach acid, pH 2 D) coffee, pH 5
What is C. Stomach acid has the lowest pH, which makes it the strongest acid.
300
When a liquid turns into a solid, which of the following also changes? A) chemical composition B) mass C) size of molecules D) energy
What is D. A liquid must lose energy to turn into a solid.
400
If battery acid spilled on the garage floor, which of the following could you use to neutralize it? A) baking soda B) vinegar C) lemon juice D) oil
What is A. Baking soda is a base that can neutralize battery acid.
400
Identify what the reactants are in a chemical reaction. A) the substances that result from the reaction B) the substances that change as a result of the reaction C) the substances that change as a result of and from the reaction D) neither the changing nor resulting substances
What is B. Reactants are substances that undergo a chemical change in a chemical reaction.
400
Copper (II) hydroxide, a blue solid, can be broken down into copper (II) oxide, a black solid, through an endothermic reaction. What happens to make this reaction occur? A) The copper (II) hydroxide is cooled. B) The copper (II) hydroxide is heated. C) The copper (II) hydroxide is mixed with another chemical. D) The copper (II) hydroxide is turned into a liquid
What is B. This reaction is endothermic, so heat must be added for it to take place.
400
A student spills soap on a piece of litmus paper, which turns blue. What does this indicate about the soap? A) It is an acid. B) It is a base. C) It is a salt. D) It is neutral.
What is B. Bases turn litmus paper blue.
400
On a humid day, water vapor in the air collects as liquid drops on the outside of a glass of ice water. What is this process called? A) evaporation B) sublimation C) solidification D) condensation
What is D. Condensation occurs when a gas changes into a liquid.
500
Which change takes place at the freezing point of a substance? A) A gas becomes a liquid. B) A solid becomes a gas. C) A liquid becomes a solid. D) A gas becomes a solid.
What is C. The freezing point is the point of change from a liquid into a solid.
500
When gasoline burns, energy is released in the form of heat and light. This is __________________ reaction. A) an endothermic B) a paleothermic C) an exothermic D) an isothermic
What is C. An exothermic reaction releases heat.
500
Before a chemical reaction, the total mass of two reactants is measured to be 40 grams. After the reaction, what should be the total mass of the products? A) 0 grams B) 20 grams C) 40 grams D) 80 grams
What is C) 40 grams.
500
Explain what happens when a strong acid and a strong base are poured into the same container. A) They form separate layers. B) They mix physically but not chemically. C) They break apart into separate elements. D) They react chemically to form a salt.
What is is D. An acid and a base combined chemically react.
500
Rubbing alcohol has a boiling point of 108°C. What happens to the alcohol molecules at this temperature? A) They disappear. B) They form a rigid, solid structure. C) They begin to move closer to one another. D) They begin to move independently from each other.
What is D. At the boiling point, the alcohol molecules move far apart from each other as they enter the gas phase.